Bash Scripting

Target Audience

• Experienced UNIX/Linux user
• System administrators who would like to save time by automating tasks.
• DevOps engineers who need to automate processes.
• Anyone who needs to make their life on UNIX

Prerequisites

• In order to take this course you must have working knowledge of the UNIX shell.
• Be able to use at least one Unix/Linux editor. Preferably Vim or Emacs.

Objectives

• To be able to write and maintain scripts written in Bash

Course Format

• Total length of the course is 16-24 academic hours. (2-3 days.)
• About 50% of the time is hands on lab work.

Syllabus

1. Bash and Bash scripts
   • Shell types
   • Advantages of Bash
   • Executing commands
   • Shell building blocks (syntax, shell commands, shell functions)
2. Writing and debugging scripts
   • Hello world
   • Creating script
   • Executing script
   • Sh-bang
   • Comments
   • Debugging
3. The Bash environment
   • Shell initialization files
   • Configuration files
   • Variables (Global and Local)
   • Creating variables
   • Using variables
   • Exporting variables
   • Strings and Quoting characters
   • Shell expansion
   • Aliases
   • Displaying and changing Options
   • Pipelines
4. Wildcards are not Regexes
   • Wildcards
   • Character Classes
5. Regular Expressions
   • grep, egrep
   • Character classes
6. sed (Stream EDitor)
   • Printing lines containing a pattern
   • Deleting lines of input containing a pattern
   • Ranges of lines
   • Find and replace with sed
7. awk (Gawk The GNU awk programming language)
   • Getting Started with awk commands
   • Printing selected fields
   • The input field separator
   • The output field separator
   • The BEGIN and END blocks
   • User defined variables
8. Control Flow and Conditional statements
   • if, then, else, fi
   • Checking command line arguments
   • Testing the number of arguments
   • Testing that a file exists
   • Comparison Operators
   • Boolean operations
   • Nested if/then Condition Tests
   • exit status codes
   • case
9. Writing interactive scripts I/O
   • Displaying user messages using echo
   • Catching user input using the read built-in command
   • Prompting for user input
   • Redirection and file descriptors
   • File input and output
   • Here documents
10. Loops for Repetitive tasks
    • The for loop
    • The while loop
    • The until loop
    • Break and continue
    • Making menus with the select built-in
    • The shift built-in
11. Types of Variables
    • Scalars
    • Arrays
    • Constants (readonly variables)
    • Operations on variables
    • Variable assignment
    • Variable substitution
12. Functions
    • Function syntax
    • Positional parameters in functions
    • Listing functions
13. Catching signals
    • What are Signals
    • How to send signals
    • Trapping signals
14. Useful shell commands
    • awk
    • cat
    • cd
    • chgrp
    • chmod
    • chown
    • cp
    • cut
    • echo
    • egrep
    • exit
    • getops
    • grep
    • head
    • ls
    • mv
    • pwd
    • sed
    • sort
    • tail
    • touch
    • uniq
    • wc

Contact

Contact: Gabor Szabo gabor@hostlocal.com
Phone: +972-54-4624648